The Application of Organic Silicone Resin Emulsion in Coating Industries

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Organic silicone emulsion coating is the room temperature solidification recyclable coating that uses water as the medium with a low VOC containment. At present, over half of organic silicone coating is non-solvent coatings which include water-based coating, macro solid molecular coating and powder coating. Besides the pure organic silicone emulsion, organic silicone emulsion coatings also have organic silicone micro emulsion, co-mixing emulsion, co-polymer emulsion and composited emulsion. Polysiloxane emulsion has negative ion type, positive ion type, non-ion type and self-emulsification type. Negative ion emulsion has better storage stability than positive ion type and it also has wider applications. To add some non-ion surface reactive agents to positive ion type, this could protect emulsion particles and enhance its stability. The organic silicone emulsions developed in recent years have slim particles and the appearance is half transparent or transparent, it also has good storage stability and excellent penetration property. The uncrosslinked organic silicone emulsion polymer is viscous inelastic rubber form matter. PDMS and other multi-functional organic silicon monomer will crosslink to be the elastic polymer weave under the effect of catalyst like organic tin.

Organic silicone coating has excellent heat resistance, weatherproof, light retention and pigment chalking resistance. However, it usually requires high temperature environment for its solidification, and the solidification is long and it is not convenient to progress on a large surface. It also has week adhesion to the bottom layer and bad solvent resistance. When in a higher temperature, the coating film will have worse mechanical properties and the price is higher. Therefore, it is always to be modified by other organic resin to make modified resins. The modification methods have two ways- physical or chemical method. The chemical modified product usually has better properties then pure physical modified product. The chemical modification mainly to lead some active functional groups to the endings or the side bases of soft polysiloxane chains of organic silicone, and then to be formed co-polymers with other macromolecule to allow organic silicone to have new applications. The organic silicone resin which is modified by other organic resins could improve its adhesion, solidification property and processing property. It could also keep organic silicone’s excellent heat resistance and weather resistance to make it more proper for the requirement from industries.

Properties of Film Polymers Made from Organic Silicone Emulsion

Emulsion coating is also called emulsion varnish, it belongs to water-based coatings. It is to use the synthetic polymer emulsion as the base material, and to add pigment, filler and other agents to form a water dispersion system.

The organic silicone emulsion that used to form film polymer is the very important component in the coating. In the dried coating layer, it takes a very large percentage and it almost influences all properties of coating. Organic silicone emulsion is color spreader, it not only has the effects like to be the adhesion pigment and to provide adhesion, toughness and integral to the dry coating film, but also the base to the coating’s final using properties like self-filming property, film transparency, weatherproof, waterproof, scrub resistance, elasticity, strong adhesion, alkaline resistance, high hardness and dirt resistance. Also, it is to reduce the cost and balance all properties of water-based coating, it is also usual to use organic silicone emulsion with some other filmed polymer like styrene emulsion and polyacrylate emulsion to make the most economic water-based coating that contains silicon polymer.

Examples of Organic Silicone Emulsion Coatings

The first type is silicone acrylic emulsion exterior coating. It is an emulsion type exterior coating that is modified by organic silicon. To compare with normal emulsion varnish, its weather proof has been improved much. At the meantime, it has the safe and non-poison properties that other coatings do not have. It also has excellent dirt resistance and chemical corrosion resistance. It will be re-stick and it will not attract dirts. Thus, it is widely used on the surfaces of concrete, steel structure, aluminum board and plastics to protect the buildings.

It is because acrylic coating has the weakness that it will be re-stick in high temperature and to be crispy in low temperature. There comes out a new type of water-based silicone propylene weatherproof self-cleaning emulsion coating that has properties like high color retention, dirt resistance, low pollution, high efficiency, low cost and could be applied in massive and high buildings. Silicone propylene exterior coating is light, high-quality and has an average price. It is the excellent high-end water-based lightless exterior coating. It is mainly used on the external coating of the base materials like cement mortar, asbestos board and plastered walls. It could also be used to coat the exterior walls of different buildings and some walls in humid environment like the inner decorations in kitchens and bathrooms.

The third type is organic elastic decorative coating It is a new material that formed by organic silicone rubber emulsion and organic macromolecular emulsion. Its filming material uses two types of co-polymer emulsion liquids as base materials. The first is the organic macromolecular emulsion includes pure acrylic acid, acetic propylene resin, styrene resin and some other kinds of polymer emulsions; it could form transparent films and has some degree of elasticity and waterproof, but it has poor adhesion to some filler. The second type of emulsion liquid is the organic silicone emulsion, it has lower surface tension, and it has good permeability on hydrophobic substances, it could form smaller touchable elastic rubber net on the surfaces of macromolecules to increase its adhesion. However, its chemical resistance and thermal stability are weak. When use two or more than two types of emulsion and allow them to be polymerized, their properties could improve each other’s weaknesses and to allow the coating have excellent adhesion, elasticity and stability.

Summary

There are more examples of organic silicone resin emulsions but it is limited to the size of the article so we only introduced three common instances. The application of organic silicone resin emulsion is definitely a successful example in industries.